Press mold for producing microcellular shaped pieces of dimensional accuracy, particularly shoe soles
US4047860A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Feb 26, 1975 |
| Grant date | Sep 13, 1977 |
| Priority date | — |
| Expiry date | Feb 26, 1995 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S425/812
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Press molds for vulcanizing plastic materials comprise a pair of mold parts defining between them a mold cavity. One of the parts is a die and the other is a cover plate that defines with the die the mold cavity. A hot liquid is introduced into a lower portion of the mold cavity through the die and gas is removed from the upper portion of the mold cavity through the cover plate. As a result, both prevulcanization and after vulcanization can be achieved in one single press mold, by surrounding the material in the mold with hot liquid in the prevulcanization and then withdrawing the liquid when the molded material fills the die cavity in the second stage of vulcanization.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.